{{ foo is empty ? 'ok' : 'ko' }}
{{ bar is empty ? 'ok' : 'ko' }}
{{ foobar is empty ? 'ok' : 'ko' }}
{{ array is empty ? 'ok' : 'ko' }}
{{ zero is empty ? 'ok' : 'ko' }}
{{ string is empty ? 'ok' : 'ko' }}
{{ countable_empty is empty ? 'ok' : 'ko' }}
{{ countable_not_empty is empty ? 'ok' : 'ko' }}
